diff options
Diffstat (limited to 'include/net/request_sock.h')
| -rw-r--r-- | include/net/request_sock.h | 12 |
1 files changed, 12 insertions, 0 deletions
diff --git a/include/net/request_sock.h b/include/net/request_sock.h index d88c0dfc2d46..ebcb8896bffc 100644 --- a/include/net/request_sock.h +++ b/include/net/request_sock.h @@ -285,4 +285,16 @@ static inline int reqsk_queue_len_young(const struct request_sock_queue *queue) return atomic_read(&queue->young); } +/* RFC 7323 2.3 Using the Window Scale Option + * The window field (SEG.WND) of every outgoing segment, with the + * exception of <SYN> segments, MUST be right-shifted by + * Rcv.Wind.Shift bits. + * + * This means the SEG.WND carried in SYNACK can not exceed 65535. + * We use this property to harden TCP stack while in NEW_SYN_RECV state. + */ +static inline u32 tcp_synack_window(const struct request_sock *req) +{ + return min(req->rsk_rcv_wnd, 65535U); +} #endif /* _REQUEST_SOCK_H */ |